It seems that Apple could be planning a similar feature for the Apple Card. According to 9to5Mac, they have discovered evidence within the iOS 14.5 beta that suggests that credit sharing could be a feature that Apple Card users can look forward to in the future, possibly with the next update.
Not much is known about this feature or how it will work exactly, but it should work pretty much how you think it would. The code also makes mention of strings that suggests that Apple Card users can also set limits to the credit that they are sharing, thus ensuring that whoever you’ve shared it with will not go over a certain limit.
We’re not sure if this means that other members of your family will get an actual physical card, or if it will be a virtual one that is linked to their phones. Either way, we’ll have to wait and see when the feature is actually launched. In the meantime, iOS 14.5 has also revealed that Apple plans on introducing financial health services, where it could study your spending habits and make recommendations on how to best save money.